Far-reaching hunter-gatherer networks during the Last Glacial Maximum in Western Europe.

Social networking is an essential feature of hunter-gatherer societies. It fosters the circulation of goods and information and enables kinship ties across different scales, including long-distance contacts. While such behaviors are known since at least the Upper Palaeolithic, evidence for geographically extensive social networks remains scarce. This evidence is limited to indirect inferences based on shared cultural traits, "art" styles, and symbolic items, while lithic raw material movements are mostly local and regional, with few cases exceeding 300 kilometers. We provide geochemical evidence for the largest confirmed distance between the source and discard location of a knapped lithic object in Palaeolithic Europe. Solutrean artifacts discarded at Peña Capón, Central Iberia, were sourced in Southwest France, 600 to 700 kilometers away. This demonstrates social networks of unprecedented geographic scale maintained during ∼1400 years during the Last Glacial Maximum. It also suggests that stone tools were exchanged as symbolic items to solidify social contacts and sustain far-reaching networks as risk-buffering mechanisms among widely dispersed hunter-gatherers.